1. Field of the Invention:
This invention relates to foamed plastic coolers having handles by which they are lifted.
2. Description of the Prior Art:
Foamed plastic coolers have become recognized as an inexpensive means for transporting food and other items at a reduced temperature. The coolers consist of a container and a top which fits snugly onto the container. The items are placed inside the container, usually with ice, and the foamed plastic walls of the container insulate the contents from the warmer temperature on the outside.
The problem most frequently encountered with foamed plastic coolers is that the handles by which they are carried usually are inadequate to permit a substantial amount of weight to be lifted. Even those handle apparatus which initially are capable of supporting a lot of weight will frequently fail within a short period of time.
The typical handle apparatus includes a plug which is inserted through the side wall of the container and which holds the supporting structure of the handle. There is usually either one handle having its ends connected to plugs in opposite sides of the container wall, or two handles, each being supported by plugs inserted within opposite sides of the container. The problem with this arrangement is that the force exerted in lifting the container by the handles is carried by only a small portion of the container walls, that portion surrounding and lying above the plugs. If a large amount of weight is carried within the container, the handle apparatus will frequently fail either by the plugs being pulled out of the container wall or by the container wall itself breaking apart above the plugs. When this occurs, the handle apparatus is made useless, and the insulating capabilities of the container are greatly reduced due to the holes through the container wall.
A second type of handle accommodation consists merely of recesses in the exterior of the side wall on opposite sides of the container. The recess is designed to permit a person's hand to grasp the container and to lift it in that manner. This design, as in the case of the plug apparatus, can fail when the container is carrying a substantial amount of weight. The portion of the container walls located above the recesses will deteriorate under the stress and will break away from the remainder of the container.
Another problem with these two handle designs is that they are not well suited to permit the container to be carried by two people. In the plug handle apparatus, either the handle plug or the container wall is likely to break away when the container is of a size and weight that requires it to be carried by two people. In addition, when two people are carrying the container, there is likely to be a less even distribution of the weight which is being supported by a particular plug held within the container wall. This is true because the less coordinated movement of two people will cause the weight which either person is carrying to vary as the container is transported. This in turn will cause the weight being supported by the individual plugs to similarly vary. As a result, the stresses applied through the plugs to the supporting wall portion of the container is likely to be greater than would normally be the case if the container was being carried by one person. This increases the likelihood that either the plug will be pulled from the container wall or the container wall will fail. Finally, when such a container is carried by two people, there will be increased horizontal stresses applied to the container wall through the supporting plug, and this additional stress will further increase the likelihood that the plug will be dislodged or the container wall will break apart.
Similarly, the recess handle apparatus is poorly suited to permit the cooler to be carried by two individuals. The recesses are generally not shaped to enable a person to carry only one end of the container. In addition, the varying stresses applied in carrying the cooler will increase the likelihood of failure of the container wall.
An additional disadvantage of the plug handle apparatus is the inability of the handle to be removed from one cooler and attached to another. Foamed plastic coolers are very susceptible to damage which renders them useless. The tops of the coolers are easily broken and the walls of the container frequently develop leaks. When this occurs, the cooler is thrown away; and the attached handle apparatus is accordingly disposed of before it has broken. The expense of the handle apparatus must, therefore, be incorporated into every cooler which is sold. In contrast, a transferable handle apparatus could be used through its entire useful life; and coolers could be sold at a lower price without handles attached.